Tim,
Paul Bruchet started with the Darne company in 1964, and worked his way up to foreman of the V Darne line. He managed to purchase the remains of the company after it was embezzeled out of existance in the late 1970s. The first guns he produced were not permitted to use the Darne name on them, anywhere, so, they were marked "Bruchet". Paul died in 2009, and had been semi-retired for some time. Permission to use the "Darne" name in the trademarked script came a few years into Paul Bruchet's production of the guns.
His son, Hervé, is still with the company, but, no longer in an ownership position.
The Bruchets would not have been associated with the Darne company at the time your gun was produced.
Also, there is nothing even remotely similar between a Halifax Darne or a boxlock of any manufacture. They are different as night is from day, and the word "boxlock" should never be used to descripe a Darne gun.
Best,
Ted
